Streaming uri_scheme_protocol

[JonasKruckenberg]

Is your feature request related to a problem? Please describe.

Streaming data back to the frontend is an important, long requested feature. It would enable new use-cases as well as drastically improve the performance of existing ones.

This issue aims to be a tracking issue for this, I plan to update it with new information.

As far as I can tell it should be possible to implement streaming responses to the webview, I don't really know if accepting streaming data coming from the webview is supported cross-platform (it's less of a priority anyway I think).

Describe the solution you'd like
Ideally we would introduce a type like hyper's Body that abstracts multiple possible sources and allows us to return synchronously produced data such as Vec<u8>, asynchronously produced data such as Future<Output = Vec<u8>> and even asynchronously multiple-return data such as Stream<Item = Vec<u8>> from a custom_uri_scheme_protocol handler.

Describe alternatives you've considered

Add a emit_data method to the UriSchemeResponder.

Would you want to assign yourself to implement this feature?

• Yes
• No

Additional context
Add any other context or screenshots about the feature request here.